Derivative Financial Instruments - Schedule of Offsetting Derivative Asset and Liability Positions (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Counterparty A
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 6,336	$ 4
Derivative Asset, Fair Value, Gross Liability	(321)	(4)
Derivative Asset, Collateral, Obligation to Return Cash, Offset	0	0
Derivative Asset	6,015	0
Derivative Liability, Fair Value, Gross Liability	321	11,025
Derivative Liability, Fair Value, Gross Asset	(321)	(4)
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	8,084
Derivative Liability	0	2,937
Counterparty B
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Asset, Fair Value, Gross Liability	0	0
Derivative Asset, Collateral, Obligation to Return Cash, Offset	0	0
Derivative Asset	0	0
Derivative Liability, Fair Value, Gross Liability	0	25
Derivative Liability, Fair Value, Gross Asset	0	0
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	0
Derivative Liability	$ 0	$ 25